Alkynes are hydrocarbons that have a triple bond between two carbon atoms, with the formula C < sub > n </ sub > H < sub > 2n-2 </ sub >.

Alkynes are traditionally known as acetylenes, although the name acetylene also refers specifically to C < sub > 2 </ sub > H < sub > 2 </ sub >, known formally as ethyne using IUPAC nomenclature.

Alkynes are usually more reactive than alkenes.

Alkynes characteristically undergo reactions that show that they are " doubly unsaturated ," meaning that each alkyne unit is capable of adding two equivalents of H < sub > 2 </ sub >, halogens or related HX reagents ( X = halide, pseudohalide, etc .).

Alkynes can be prepared from aldehydes using the Corey-Fuchs reaction and from aldehydes or ketones by the Seyferth – Gilbert homologation.

Alkynes undergo diverse cycloaddition reactions.

Alkynes occur in some pharmaceuticals, including the contraceptive norethynodrel.

Alkynes react similarly, forming the tetrahalo compounds.

Finally, the theatrical ( and perversely erotic ) notions of dressing up, cosmetics, disguise, and especially change of costume ( or singularity of costume, as with Cipolla ), are characteristically associated with the catastrophes of Mann's stories.

Key evidence of Baltic language presence in these regions is found in hydronyms ( names of bodies of water ) in the regions that are characteristically Baltic.

Lang's magnum opus, M — released in 1931, two years before his departure from Germany — is among the first major crime films of the sound era to join a characteristically noirish visual style with a noir-type plot, one in which the protagonist is a criminal ( as are his most successful pursuers ).

The ears are rather long and slightly curved inward, characteristically known as " banana " shaped.

Circularization is thought to promote cycling of ribosomes on the mRNA leading to time efficient translation, and may also function to ensure only intact mRNA are translated ( partially degraded mRNA characteristically have no m7G cap, or no poly-A tail ).

Substantially longer than wide and characteristically employed in pairs, skis are attached to boots with bindings, either with a free, lockable, or permanently secured heel.

All hormones that act by regulation of gene expression have two consequences in their mechanism of action ; their effects are produced after a characteristically long period of time and their effects persist for another long period of time, even after their concentration has been reduced to zero, due to a relatively slow turnover of most enzymes and proteins that would either deactivate or terminate ligand binding onto the receptor.

Some switches are light switches which can be used to turn off the lights in the respective level, making some enemies characteristically afraid to jump.

Eurobonds are characteristically underwritten, and not secured, and interest is paid gross.

Domine praestolamur ( 1589 ) is a good example of this style, laid out in imitative paragraphs based on subjects which characteristically emphasize the expressive minor second and minor sixth, with continuations which subsequently break off and are heard separately ( another technique which Byrd had learnt from his study of Ferrabosco ).

Although mature Eucalyptus trees are usually towering and fully leafed, their shade is characteristically patchy because the leaves usually hang downwards.

Flowers of Poaceae are characteristically arranged in spikelets, each spikelet having one or more florets.

These tics characteristically wax and wane, can be suppressed temporarily, and are preceded by a premonitory urge.

Waxes are organic compounds that characteristically consist of long alkyl chains.

Although classified as eukaryotes, the dinoflagellate nuclei are not characteristically eukaryotic, as they lack histones, nucleosomes and maintain continually condensed chromosomes during mitosis.

Ammonoid septa characteristically have bulges and indentations and are to varying degrees convex from the front, distinguishing them from nautiloid septa which are typically simple concave dish-shaped structures.

Coppiced stems are characteristically curved at the base.

Their albums are also notable for the characteristically ' warm ' and ' dry ' production sound, and the sparing use of echo and reverberation.

In laymen's terms, quantization is a method for optimally reducing a large number scale ( with different occurrences of each number ) into a smaller one, and the transform-domain is a convenient representation of the image because the high-frequency coefficients, which contribute less to the over picture than other coefficients, are characteristically small-values with high compressibility.

This palette can mix all possible hues, though the purple, orange and green mixtures are characteristically rather dull or dark, and most color mixtures require use of all three paints.

Also parts of his dress, with rows of geometrical folds, are characteristically Hellenistic in style.

Extrusomes are characteristically in the form of spindle trichocysts, which release thread-like shafts, and never mucocysts.

Or, more rhythmically, ' The swarthy witches are laughing '??

but four Eromonga women are more than a match for the strongest male that ever lived.

But in our case -- and neither my wife nor I have extreme views on integration, nor are we given to emotional outbursts -- the situation has ruined one or two valued friendships and come close to wrecking several more.

I suspect that there are far more unreconstructed ones than the North likes to believe.

Old attitudes are held more tenaciously in the Tidewater than the Piedmont ; ;

Only one rule prevailed in my conversations with these men: The more highly placed they are -- that is, the more they know -- the more concerned they have become.

On Fridays, the day when many Persians relax with poetry, talk, and a samovar, people do not, it is true, stream into Chehel Sotun -- a pavilion and garden built by Shah Abbas 2, in the seventeenth century -- but they do retire into hundreds of pavilions throughout the city and up the river valley, which are smaller, more humble copies of the former.

But more important, and the thing which the casual traveler and the blind sojourner often do not see, is that these places and activities are often the settings in which Persians exercise their extraordinary aesthetic sensibilities.

Nostalgic Yankee readers of Erskine Caldwell are today informed by proud Georgians that Tobacco Road is buried beneath a four-lane super highway, over which travel each day suburbanite businessmen more concerned with the Dow-Jones average than with the cotton crop.

We get some clue from a few remembrances of childhood and from the circumstance that we are probably not much more afraid of people now than man ever was.

Even in domains where detailed and predictive understanding is still lacking, but where some explanations are possible, as with lightning and weather and earthquakes, the appropriate kind of human action has been more adequately indicated.

These my grandmother left in their places ( they are still there, more persistent and longer-lived than the generations of man ) and planted others like them, that flourished without careful tending.

The Poetics, in affirming that all human arts are `` modes of imitation '', gives a more serious role to artistic mimesis than did Plato.

The state universities of Maine, New Hampshire, And Vermont are older and more `` respectable '' ; ;

Among the recipients of the Nobel Prize for Literature more than half are practically unknown to readers of English.

Of these there are surely few that would be more rewarding discoveries than Verner Von Heidenstam, the Swedish poet and novelist who received the award in 1916 and whose centennial was celebrated two years ago.

All four types of message listed in Table 1 are permitted, although decorum and cocktail tradition require holding the commands to a minimum, while exclamations having complimentary intonations are more than customarily encouraged.

In contrast to cocktail parties, military organizations, even in the field, are more formal.

Have not our physical abilities already deteriorated because of the more sedentary lives we are now living??

What is more, the legends have become so sacrosanct that the very habit of self-examination or self-criticism smells of low treason, and men who practice it are defeatists and unpatriotic scoundrels.

and the laughter and the happiness are even more pronounced when no company is present.

but they are important foundation stones for more extensive exploration of outer space for the ultimate benefit of all mankind.